This invention relates to a stuffing-dosing machine for pasty food products such as, namely, whole, chopped and sliced meat or meat mass, cheeses, fine pastes and jams, of the type comprising: a container for a food product which may be sealed in which vacuum is produced; means for removing said food product and impelling it towards stuffing-dosing chambers; two alternating stuffing cylinders, to push, by means of related pistons, the food product from the stuffing chamber; collecting ducts and a rotatory collecting-stuffing valve, the motion of which is synchronized with that of said stuffing cylinders to alternatively let pass the food product impelled by one or the other cylinder, so that it results in a single virtually continuous flow of said food product at the outlet of said collecting-distributing valve.
Machines of this type are largely well-known, and there may be noted namely as background of patents U.S. Pat. Nos. 3,868,048, 4,533,300 and applications for patent WO-A-89/03479, WO-A-95/30087, WO-A-96/06029, WO-A-96/07327 and WO-A-96/14492.
In all of them, assemblies provided with two alternatively operating pistons are disclosed, having a collecting system and a distributing valve, and correspond to applications for food industry and namely for meat industry.
The principle of transferring pasty products by means of two cylinders having alternatively operating pistons is well-known and so patent ES-A-8400550 discloses a machine having said characteristic for handling concrete.
Patent WO-A-95/30087 discloses with details a rotatory valve for a double piston pump, provided with a device which facilitates rotor withdrawal to proceed to clean said valve.
Patent WO-A-96/07327 discloses a pump for food products coming from a container in which vacuum has been produced, provided with two alternative motion pistons and a rotatory valve of above mentioned type, as well as a system to control both pistons speed and run path.
In said pump the two cylinders are arranged parallel to each other in horizontal position so that recesses where said cylinders respective pistons or piston heads operate remain open at their top, immediately under the outlet of a container of food product under vacuum, provided with means to remove and impel said product toward said recesses. Each cylinder has available an external moving lining which acts in a first step closing and defining a stuffing chamber within which related piston acts in a second step. Two conducting ducts each connected to the outlet of one of the stuffing chambers converge in a rotatory valve having a motion synchronized with that of both pistons which provides alternatively passage to food product coming from one or the other conducting duct toward a single output duct from which a continuous flow of said food product is obtained.
This arrangement has the drawback to have a great complexity of mechanisms with reference to duplicating operations for each piston and its related external moving lining and because of the mechanisms of the means to remove and impel food product within the container toward stuffing recesses. Also it has the drawback to require much room because of the horizontal arrangement, external to the container, of the cylinders, the existence of the two conducting ducts, and the side arrangement of the two conducting ducts inlets to the rotatory valve which requires a large gap between them.
The object of this invention is to overcome said drawbacks providing a stuffing-dosing machine for pasty food products having quite simple mechanisms a compact design and easy cleaning, including less moving parts and in addition an operating cycle having less number of steps and therefore speedier.
This object is achieved in a machine according to this invention the basic characteristics of which are disclosed in claim 1.
The invention is inspired in a structure of a machine of this type disclosed in patent ES-A-2015660 of the same applicant where is disclosed the use of an hydraulic cylinder the piston of which is inserted up to the interior of the recess of a vacuum tight container and is ended in a faller-like plate, to push meat masses toward a stuffing recess.
The machine involved comprises now a vacuum food product container having two stuffing cylinders located in tilted position, parallel and close to each other, forming a small angle with the vertical and outside the container, housed in a hollow of its side walls so that their related piston bodies and heads directly act within said container. In a first length of their respective two direction runs said pistons act removing making easier entrapped air exhaust and impelling the mass of food product contained in a narrowed area (frustum-shaped in the example of embodiment disclosed thereafter) of the container bottom towards two stuffing-dosing chambers located at the bottom of said container each of said chambers being coaxially aligned with the axis of a respective piston. Within said two chambers, the pistons perform a second length of their runs, very accurately controlled by regulating means with their respective piston heads adjusted to the internal walls of said chambers, with which food product stuffing and dosing functions are performed.
In order to provide a continuous flow of food product during a predetermined time of operation of the alternative driven pistons a rotatory valve let alternatively pass, in a synchronized way with respect to the pistons action, the food product coming from one or the other stuffing-dosing chamber. Said valve is located directly under said stuffing-dosing chambers and interposed between respective compacting-stuffing recesses which remain coaxially aligned with said stuffing-dosing chambers which they extend. So a third cylindric recess is located between the two compacting and stuffing recesses, forming a certain tilting angle with respect to them, so that it intersects both in same way forming respective communication openings. A cylindric valve body provided with a side port may rotate by sliding within said third recess so that, impelled by an alternative drive such as an hydraulic motor, said port remains alternatively facing each of said communication openings. This way, through the outlet of the third cylindric recess a continuous flow of food product is produced which may be stuffed and lead for example to a vacuum sealing station to a thermoforming station or any other machine for complementary operations of product finishing and packing.
In the machine according to the invention, piston speed, run path and alternation as well as valve synchronization are adjustable. Thus by programming an indefinitely repeated given cycle a continuous flow production is achieved. On the contrary, by programming cycles composed of complete pistons actions or fractions thereof, with discrete stops between said cycles a production in separate portions is achieved with amounts accurately dosed.
The food product goes into said container using the suction force itself provided by the vacuum existing within said container, as already applied to the machine disclosed in said patent ES-A-2015660 of the applicant himself.
Means have been provided to control the level within the container between a maximum and a minimum in order that in the moment the meat has access to the stuffing-dosing chambers an essentially constant pressure is achieved.
Also side ports have been provided, which have advantageously transparent covers, which allows the access within the container for its cleaning and the pistons are removable, connectable with a straightforward junction to related cylinder rod or moving body, to facilitate the assembly periodical cleaning task.
Summarizing above disclosed, we have that:
First, the two pistons driving cylinders are located in a tilted position close to the vertical, outside the container preventing any contamination problem.
Second, the rods or moving bodies and the piston heads of said cylinders directly act within said container. This way, in a first length of their run, said piston heads perform their function of removing, facilitating entrapped air exhaust and downwardly impelling the food product which is located in the narrowed area of the bottom of said container, therefore other additional mechanisms are not required to carry out such tasks, as those incorporated in the apparatuses disclosed in above patents background.
Third, the special shape of the rotatory valve of a machine according to the invention easily dismounted for cleaning makes possible that stuffing-dosing chambers are located so close to each other as the very geometry allows it. In addition, thanks to the location of the valve immediately under said chambers and embedded between the compacting-stuffing recesses additional conduction ducts the former models incorporated result unnecessary from said chambers up to the valve body.
Last, by providing level control means in the container they guarantee an even pressure of meat or other pasty product in the moment of having access to the stuffing chambers.
The advantages of a machine according to the invention with respect to the former ones consist in reducing mechanisms, drives and moving parts which means a great compactness of said machine and a simple and safe operation, easy cleaning and servicing, obtaining a higher performance by shortening the stuffing cycle.
To best understand the invention a detailed description is found below with reference to the drawings attached, said drawings being for sole illustration purpose of a possible embodiment of the invention which in no case must be purported as limitating it.